1. Grasslands are the richest of biologic zones. European temperatue forests are mostly oak which loose their leaves in winter. Northern confier forests either loose leaves (larch) or just slow down. Most of their activity is in the spring and summer but their activity is nothing compared to grassland which is what farmland is.

2. The Little Ice Age was worldwide, not confined to Europe. A much broader, stronger mechanism is needed to explain this, not just change of activity in on region.

3. Given #2, what is the real difference in gasseous activity between forest and grassland in Europe alone? It is this figure which is under discussion.

1. Grasslands are the richest of biologic zones. European temperatue forests are mostly oak which loose their leaves in winter. Northern confier forests either loose leaves (larch) or just slow down. Most of their activity is in the spring and summer but their activity is nothing compared to grassland which is what farmland is.

Forests have more standing biomass than grassland. If land reforests, it sucks CO2 out of the air.

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2. The Little Ice Age was worldwide, not confined to Europe. A much broader, stronger mechanism is needed to explain this, not just change of activity in on region.

Eh? If Europe reforested massively it would suck in CO2 from the whole atmosphere, not just the bit over Europe. Winds, you know, and stuff.

The Tree / CO2 relationship effects global temperature, it's not restricted locally. If the Earth cooled 2 deg over the next 50 years, the polar regions would be cooler than what they are now, so would Brazil. However, as said Brazil is near the Equator, the Polar regions is where the Ice Age would occur.

Forests have more standing biomass than grassland. If land reforests, it sucks CO2 out of the air.

Eh? If Europe reforested massively it would suck in CO2 from the whole atmosphere, not just the bit over Europe. Winds, you know, and stuff.

Standing biomass is not the issue. The issue is active biomass. Grasslands are the most active biological zones in terms of atmospheric chemistry. Most forest wood is dead and so inert. Grass renews each year bringing a burst of oxygen and reduction in carbon dioxide.

"Europe reforested massively"? Europe is what 15% of the total land mass? In terms of active biomass, it is not even a big player. Asia, North America, South America and Africa (maybe Australia) are all more chemically active than Europe in terms of atmospherics.

OK, let's assume this hypothesis is correct. In North America today something very similar is happening. Pasture and farm land in the Eastern USA and Southern Canada has gone fallow and the process has been going on for 50 years. Cows are now milked in feed pens near urban areas, mostly in the arid Southwest. Wheat, corn, soybeans, etc. are now grown in large commerical farms using irrigation. The family farm is gone. These areas are now overgrown and returning to forest all across the Northeast. In the Western USA, since the coming of the White man, our forests have gone wild. Pictures 100 years ago vs pictures now clearly show this everwhere. These combined areas have a great deal more forested land than Europe and more change. So where is the cooling climate change?

OK, let's assume this hypothesis is correct. In North America today something very similar is happening. Pasture and farm land in the Eastern USA and Southern Canada has gone fallow and the process has been going on for 50 years. Cows are now milked in feed pens near urban areas, mostly in the arid Southwest. Wheat, corn, soybeans, etc. are now grown in large commerical farms using irrigation. The family farm is gone. These areas are now overgrown and returning to forest all across the Northeast. In the Western USA, since the coming of the White man, our forests have gone wild. Pictures 100 years ago vs pictures now clearly show this everwhere. These combined areas have a great deal more forested land than Europe and more change. So where is the cooling climate change?

This theory we are discussing isn't worth passionate argument, but the reply to this is that CO2 in the air is currently increasing despite reforestation, as direct measurements show.